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25-532: The Tamaricaceae , the tamarisk family, are a family of plants native to drier areas of Europe, Asia, and Africa. It contains four genera : Tamarix (with 73 species), Reaumuria (25 species), Myricaria (13 species), and Myrtama (a single species). In the 1980s, the family was classified in the Violales under the Cronquist system ; more modern classifications ( Angiosperm Phylogeny Group ) place them in

50-583: A distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles , adults are immobile but their larvae are mobile, and use their mobile larval form to distribute themselves. These larvae used for dispersal are either planktotrophic (feeding) or lecithotrophic (non-feeding) . Some larvae are dependent on adults to feed them. In many eusocial Hymenoptera species,

75-620: A large evergreen tree, does not sexually reproduce in the local climate and is not considered a seriously invasive species. The Athel tree is commonly used for windbreaks on the edge of agricultural fields and as a shade tree in the deserts of the Southwestern United States. The second subgroup contains the deciduous tamarisks, which are small, shrubby trees, commonly known as "saltcedars". These include T. pentandra , T. tetrandra , T. gallica , T. chinensis , T. ramosissima and T. parviflora . Larva A larva's appearance

100-485: A significant invasive plant species . In other areas, the plants form dense monocultures that alter the natural environment and compete with native species already stressed by human activity. Recent scientific investigations have generally concluded that the primary human-caused impact to desert riparian ecosystems within the Colorado River Basin is the alteration of the flood regime by dams; Tamarix ramosissima

125-481: A small capsule usually adorned with a tuft of hair that aids in wind dispersal. Seeds can also be dispersed by water. Seedlings require extended periods of soil saturation for establishment. Tamarisk trees are most often propagated by cuttings . These trees grow in disturbed and undisturbed streams, waterways, bottom lands, banks, and drainage washes of natural or artificial water bodies, moist rangelands and pastures. Whether Tamarix species are fire-adapted or not

150-404: A small soil sample from areas where Tamarix trees grew was mixed in with the potting soil, as opposed to samples without these plants. This was thought to indicate the presence of beneficial mycorrhizae . The presence of Tamarix plants has also been shown to boost soil fertility in a number of studies, and it also increases soil salinity. Two studies found that Tamarix plants are able to limit

175-518: Is an evergreen tree that can grow to 18 m (59 ft) tall. They usually grow on saline soils , tolerating up to 15,000 ppm soluble salt , and can also tolerate alkaline conditions. Tamarisks are characterized by slender branches and grey-green foliage. The bark of young branches is smooth and reddish brown. As the plants age, the bark becomes gray-brown, ridged and furrowed. The leaves are scale-like, almost like that of junipers, 1–2 mm (1/20" to 1/10") long, and overlap each other along

200-599: Is composed of about 50–60 species of flowering plants in the family Tamaricaceae , native to drier areas of Eurasia and Africa . The generic name originated in Latin and may refer to the Tamaris River in Hispania Tarraconensis ( Spain ). They are evergreen or deciduous shrubs or trees growing to 1–18 m ( 3 + 1 ⁄ 2 –59 ft) in height and forming dense thickets. The largest, Tamarix aphylla ,

225-561: Is generally very different from the adult form ( e.g. caterpillars and butterflies ) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. In the case of smaller primitive arachnids, the larval stage differs by having three instead of four pairs of legs. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs . By living in

250-411: Is relatively tolerant of this hydrologic alteration compared to flood-dependent native woody riparian species such as willow , cottonwood , and box elder . Research on competition between tamarisk seedlings and co-occurring native trees has found that Tamarix seedlings are not competitive over a range of environments, but stands of mature trees effectively prevent native species' establishment in

275-476: Is unclear, but in many cases a large proportion of the trees are able to resprout from the stump after fires, although not notably more so than other riverine species. They likely cannot resprout from root suckers. In some habitats where they are native, wildfire appears to favour the establishment of riverine trees such as Populus , to the detriment of Tamarix . Conversely, they do appear to be more flammable, with more dead wood produced and debris held aloft. In

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300-552: The Caryophyllales . Many of the plants in the family grow on saline soils , tolerating up to 15,000 ppm soluble salt and can also tolerate alkaline conditions. The leaves are generally scale-like, measure 1–5 mm long, overlap each other along the stem, and in some species are encrusted with salt secretions. This Caryophyllales article is a stub . You can help Misplaced Pages by expanding it . Tamarisk See text The genus Tamarix ( tamarisk , salt cedar , taray )

325-522: The germination of a number of native plants. However, a study involving more than a thousand soil samples across gradients of both flood frequency and Tamarix density concluded that "flooding may be the most important factor for assessing floodplain salinity" and "soils under Tamarix canopies had lower surface soil salinity than open areas deprived of flooding suggesting that surface evaporation may contribute more to surface soil salinity than Tamarix ". Tamarix species are commonly believed to disrupt

350-587: The understory , due to low light, elevated salinity, and possibly changes to the soil biota . Box elder ( Acer negundo , a native riparian tree) seedlings survive and grow under higher-shade conditions than Tamarix seedlings, and mature Tamarix specimens die after 1–2 years of 98% shade, indicating a pathway for successional replacement of Tamarix by box elder. Anthropogenic activities that preferentially favor tamarisk (such as changes to flooding regimens) are associated with infestation. To date, Tamarix has taken over large sections of riparian ecosystems in

375-425: The habitat is altered by controlling flood regimes and disturbance of water sources. Because the trees are able to concentrate salts on the outside of their leaves, dense stands of the tree will form a layer of high salinity on the topsoil as the leaves are shed. Although this layer is easily washed off during flooding events, in areas where the rivers are channelled and floods are controlled, this salty layer inhibits

400-407: The larvae are fed by female workers. In Ropalidia marginata (a paper wasp) the males are also capable of feeding larvae but they are much less efficient, spending more time and getting less food to the larvae. The larvae of some organisms (for example, some newts ) can become pubescent and do not develop further into the adult form. This is a type of neoteny . It is a misunderstanding that

425-520: The larval form always reflects the group's evolutionary history . This could be the case, but often the larval stage has evolved secondarily, as in insects. In these cases , the larval form may differ more than the adult form from the group's common origins. Within Insects , only Endopterygotes show complete metamorphosis, including a distinct larval stage. Several classifications have been suggested by many entomologists , and following classification

450-547: The national park system. Various attempts to control tamarisk have been implemented on federal lands including Dinosaur National Monument , San Andres National Wildlife Refuge , and White Sands Missile Range . After years of study, the USDA Agricultural Research Service found that the introduced tamarisk beetles ( Diorhabda elongata ) eat only the tamarisk, and starve when no more is available, not eating any plants native to North America. The tamarisk

475-427: The recruitment of Salix and Populus tree species, in the latter case possibly due to interfering with the trees ability to form symbiotic relationships with arbuscular mycorrhizal fungi, in contrast to the grass and legume species studied in 2013. Because it is much more efficient at both obtaining water from drying soil and conserving water during drought, it can outcompete many native species, especially after

500-522: The southwestern USA, most stands studied appear to be burning at faster intervals than they can fully mature and die of natural causes. Tamarix species are used as food plants by the larvae of some Lepidoptera species including Coleophora asthenella which feeds exclusively on T. africana . In some specific riparian habitats in the Southwestern United States and California , Tamarix ramosissima has naturalized and become

525-518: The stem. They are often encrusted with salt secretions. The pink to white flowers appear in dense masses on 5–10 cm (2" to 4") long spikes at branch tips from March to September, though some species (e.g., T. aphylla ) tend to flower in the summer until as late as November. Tamarix aphylla can spread both vegetatively , by submerged stems producing adventitious roots, and sexually, by seeds . Each flower can produce thousands of tiny (1 mm; 1/20" diameter) seeds that are contained in

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550-534: The structure and stability of North American native plant communities and degrade native wildlife habitat, by outcompeting and replacing native plant species, salinizing soils, monopolizing limited sources of moisture, and increasing the frequency, intensity, and effect of fires and floods . While individual plants may not consume larger quantities of water than native species, large, dense stands of tamarisk do consume more water than equivalent stands of native cottonwoods . An active and ongoing debate exists as to when

575-533: The tamarisk can out-compete native plants, and if it is actively displacing native plants or it just taking advantage of disturbance by removal of natives by humans and changes in flood regimens. Pest populations of tamarisk in the United States can be dealt with in several ways. The National Park Service has used the methods of physically removing the plants, spraying them with herbicides , and introducing northern tamarisk beetles ( Diorhabda carinulata ) in

600-421: The western United States that were once home to native cottonwoods and willows, and are projected by some to spread well beyond the current range. In a 2013 study which examined if native plant growth was hindered by the microbiota associated with the presence of Tamarix , a relatively new invasive plant to the northern United States, Elymus lanceolatus and other native plants in fact grew better when

625-705: Was introduced to the United States as an ornamental shrub, a windbreak , and a shade tree in the early 19th century. In the 1930s, during the Great Depression, tree-planting was used as a tool to fight soil erosion on the Great Plains, and different trees were planted by the millions in the Great Plains Shelterbelt , including salt cedars. Eight species are found in North America. They can be divided into two subgroups: Tamarix aphylla (Athel tree),

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